/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*

 * Implementation of DOMTokenList specified by HTML5.

 */

#include "nsDOMTokenList.h"

#include "nsAttrValue.h"

#include "nsAttrValueInlines.h"

#include "nsDataHashtable.h"

#include "nsError.h"

#include "nsHashKeys.h"

#include "mozilla/dom/Element.h"

#include "mozilla/dom/DOMTokenListBinding.h"

#include "mozilla/BloomFilter.h"

#include "mozilla/ErrorResult.h"

using namespace mozilla;

using namespace mozilla::dom;

nsDOMTokenList::nsDOMTokenList(Element* aElement, nsAtom* aAttrAtom,

                               const DOMTokenListSupportedTokenArray aSupportedTokens)

  : mElement(aElement),

    mAttrAtom(aAttrAtom),

    mSupportedTokens(aSupportedTokens)

{

  // We don't add a reference to our element. If it goes away,

  // we'll be told to drop our reference

}

nsDOMTokenList::~nsDOMTokenList() { }

NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(nsDOMTokenList, mElement)

NS_INTERFACE_MAP_BEGIN(nsDOMTokenList)

  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY

  NS_INTERFACE_MAP_ENTRY(nsISupports)

  NS_INTERFACE_MAP_ENTRIES_CYCLE_COLLECTION(nsDOMTokenList)

NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTING_ADDREF(nsDOMTokenList)

NS_IMPL_CYCLE_COLLECTING_RELEASE(nsDOMTokenList)

const nsAttrValue*

nsDOMTokenList::GetParsedAttr()

{

  if (!mElement) {

    return nullptr;

  }

  return mElement->GetAttrInfo(kNameSpaceID_None, mAttrAtom).mValue;

}

void

nsDOMTokenList::RemoveDuplicates(const nsAttrValue* aAttr)

{

  if (!aAttr || aAttr->Type() != nsAttrValue::eAtomArray) {

    return;

  }

  BloomFilter<8, nsAtom> filter;

  AtomArray* array = aAttr->GetAtomArrayValue();

  for (uint32_t i = 0; i < array->Length(); i++) {

    nsAtom* atom = array->ElementAt(i);

    if (filter.mightContain(atom)) {

      // Start again, with a hashtable

      RemoveDuplicatesInternal(array, i);

      return;

    } else {

      filter.add(atom);

    }

  }

}

void

nsDOMTokenList::RemoveDuplicatesInternal(AtomArray* aArray, uint32_t aStart)

{

  nsDataHashtable<nsPtrHashKey<nsAtom>, bool> tokens;

  for (uint32_t i = 0; i < aArray->Length(); i++) {

    nsAtom* atom = aArray->ElementAt(i);

    // No need to check the hashtable below aStart

    if (i >= aStart && tokens.Get(atom)) {

      aArray->RemoveElementAt(i);

      i--;

    } else {

      tokens.Put(atom, true);

    }

  }

}

uint32_t

nsDOMTokenList::Length()

{

  const nsAttrValue* attr = GetParsedAttr();

  if (!attr) {

    return 0;

  }

  RemoveDuplicates(attr);

  return attr->GetAtomCount();

}

void

nsDOMTokenList::IndexedGetter(uint32_t aIndex, bool& aFound, nsAString& aResult)

{

  const nsAttrValue* attr = GetParsedAttr();

  if (!attr || aIndex >= static_cast<uint32_t>(attr->GetAtomCount())) {

    aFound = false;

    return;

  }

  RemoveDuplicates(attr);

  if (attr && aIndex < static_cast<uint32_t>(attr->GetAtomCount())) {

    aFound = true;

    attr->AtomAt(aIndex)->ToString(aResult);

  } else {

    aFound = false;

  }

}

void

nsDOMTokenList::SetValue(const nsAString& aValue, ErrorResult& rv)

{

  if (!mElement) {

    return;

  }

  rv = mElement->SetAttr(kNameSpaceID_None, mAttrAtom, aValue, true);

}

nsresult

nsDOMTokenList::CheckToken(const nsAString& aStr)

{

  if (aStr.IsEmpty()) {

    return NS_ERROR_DOM_SYNTAX_ERR;

  }

  nsAString::const_iterator iter, end;

  aStr.BeginReading(iter);

  aStr.EndReading(end);

  while (iter != end) {

    if (nsContentUtils::IsHTMLWhitespace(*iter))

      return NS_ERROR_DOM_INVALID_CHARACTER_ERR;

    ++iter;

  }

  return NS_OK;

}

nsresult

nsDOMTokenList::CheckTokens(const nsTArray<nsString>& aTokens)

{

  for (uint32_t i = 0, l = aTokens.Length(); i < l; ++i) {

    nsresult rv = CheckToken(aTokens[i]);

    if (NS_FAILED(rv)) {

      return rv;

    }

  }

  return NS_OK;

}

bool

nsDOMTokenList::Contains(const nsAString& aToken)

{

  const nsAttrValue* attr = GetParsedAttr();

  return attr && attr->Contains(aToken);

}

void

nsDOMTokenList::AddInternal(const nsAttrValue* aAttr,

                            const nsTArray<nsString>& aTokens)

{

  if (!mElement) {

    return;

  }

  nsAutoString resultStr;

  if (aAttr) {

    RemoveDuplicates(aAttr);

    for (uint32_t i = 0; i < aAttr->GetAtomCount(); i++) {

      if (i != 0) {

        resultStr.AppendLiteral(" ");

      }

      resultStr.Append(nsDependentAtomString(aAttr->AtomAt(i)));

    }

  }

  AutoTArray<nsString, 10> addedClasses;

  for (uint32_t i = 0, l = aTokens.Length(); i < l; ++i) {

    const nsString& aToken = aTokens[i];

    if ((aAttr && aAttr->Contains(aToken)) ||

        addedClasses.Contains(aToken)) {

      continue;

    }

    if (!resultStr.IsEmpty()) {

      resultStr.Append(' ');

    }

    resultStr.Append(aToken);

    addedClasses.AppendElement(aToken);

  }

  mElement->SetAttr(kNameSpaceID_None, mAttrAtom, resultStr, true);

}

void

nsDOMTokenList::Add(const nsTArray<nsString>& aTokens, ErrorResult& aError)

{

  aError = CheckTokens(aTokens);

  if (aError.Failed()) {

    return;

  }

  const nsAttrValue* attr = GetParsedAttr();

  AddInternal(attr, aTokens);

}

void

nsDOMTokenList::Add(const nsAString& aToken, ErrorResult& aError)

{

  AutoTArray<nsString, 1> tokens;

  tokens.AppendElement(aToken);

  Add(tokens, aError);

}

void

nsDOMTokenList::RemoveInternal(const nsAttrValue* aAttr,

                               const nsTArray<nsString>& aTokens)

{

  MOZ_ASSERT(aAttr, "Need an attribute");

  RemoveDuplicates(aAttr);

  nsAutoString resultStr;

  for (uint32_t i = 0; i < aAttr->GetAtomCount(); i++) {

    if (aTokens.Contains(nsDependentAtomString(aAttr->AtomAt(i)))) {

      continue;

    }

    if (!resultStr.IsEmpty()) {

      resultStr.AppendLiteral(" ");

    }

    resultStr.Append(nsDependentAtomString(aAttr->AtomAt(i)));

  }

  mElement->SetAttr(kNameSpaceID_None, mAttrAtom, resultStr, true);

}

void

nsDOMTokenList::Remove(const nsTArray<nsString>& aTokens, ErrorResult& aError)

{

  aError = CheckTokens(aTokens);

  if (aError.Failed()) {

    return;

  }

  const nsAttrValue* attr = GetParsedAttr();

  if (!attr) {

    return;

  }

  RemoveInternal(attr, aTokens);

}

void

nsDOMTokenList::Remove(const nsAString& aToken, ErrorResult& aError)

{

  AutoTArray<nsString, 1> tokens;

  tokens.AppendElement(aToken);

  Remove(tokens, aError);

}

bool

nsDOMTokenList::Toggle(const nsAString& aToken,

                       const Optional<bool>& aForce,

                       ErrorResult& aError)

{

  aError = CheckToken(aToken);

  if (aError.Failed()) {

    return false;

  }

  const nsAttrValue* attr = GetParsedAttr();

  const bool forceOn = aForce.WasPassed() && aForce.Value();

  const bool forceOff = aForce.WasPassed() && !aForce.Value();

  bool isPresent = attr && attr->Contains(aToken);

  AutoTArray<nsString, 1> tokens;

  (*tokens.AppendElement()).Rebind(aToken.Data(), aToken.Length());

  if (isPresent) {

    if (!forceOn) {

      RemoveInternal(attr, tokens);

      isPresent = false;

    }

  } else {

    if (!forceOff) {

      AddInternal(attr, tokens);

      isPresent = true;

    }

  }

  return isPresent;

}

bool

nsDOMTokenList::Replace(const nsAString& aToken,

                        const nsAString& aNewToken,

                        ErrorResult& aError)

{

  // Doing this here instead of using `CheckToken` because if aToken had invalid

  // characters, and aNewToken is empty, the returned error should be a

  // SyntaxError, not an InvalidCharacterError.

  if (aNewToken.IsEmpty()) {

    aError.Throw(NS_ERROR_DOM_SYNTAX_ERR);

    return false;

  }

  aError = CheckToken(aToken);

  if (aError.Failed()) {

    return false;

  }

  aError = CheckToken(aNewToken);

  if (aError.Failed()) {

    return false;

  }

  const nsAttrValue* attr = GetParsedAttr();

  if (!attr) {

    return false;

  }

  return ReplaceInternal(attr, aToken, aNewToken);

}

bool

nsDOMTokenList::ReplaceInternal(const nsAttrValue* aAttr,

                                const nsAString& aToken,

                                const nsAString& aNewToken)

{

  RemoveDuplicates(aAttr);

  // Trying to do a single pass here leads to really complicated code.  Just do

  // the simple thing.

  bool haveOld = false;

  for (uint32_t i = 0; i < aAttr->GetAtomCount(); ++i) {

    if (aAttr->AtomAt(i)->Equals(aToken)) {

      haveOld = true;

      break;

    }

  }

  if (!haveOld) {

    // Make sure to not touch the attribute value in this case.

    return false;

  }

  bool sawIt = false;

  nsAutoString resultStr;

  for (uint32_t i = 0; i < aAttr->GetAtomCount(); i++) {

    if (aAttr->AtomAt(i)->Equals(aToken) ||

        aAttr->AtomAt(i)->Equals(aNewToken)) {

      if (sawIt) {

        // We keep only the first

        continue;

      }

      sawIt = true;

      if (!resultStr.IsEmpty()) {

        resultStr.AppendLiteral(" ");

      }

      resultStr.Append(aNewToken);

      continue;

    }

    if (!resultStr.IsEmpty()) {

      resultStr.AppendLiteral(" ");

    }

    resultStr.Append(nsDependentAtomString(aAttr->AtomAt(i)));

  }

  MOZ_ASSERT(sawIt, "How could we not have found our token this time?");

  mElement->SetAttr(kNameSpaceID_None, mAttrAtom, resultStr, true);

  return true;

}

bool

nsDOMTokenList::Supports(const nsAString& aToken,

                         ErrorResult& aError)

{

  if (!mSupportedTokens) {

    aError.ThrowTypeError<MSG_TOKENLIST_NO_SUPPORTED_TOKENS>(

      mElement->LocalName(),

      nsDependentAtomString(mAttrAtom));

    return false;

  }

  for (DOMTokenListSupportedToken* supportedToken = mSupportedTokens;

       *supportedToken;

       ++supportedToken) {

    if (aToken.LowerCaseEqualsASCII(*supportedToken)) {

      return true;

    }

  }

  return false;

}

void

nsDOMTokenList::Stringify(nsAString& aResult)

{

  if (!mElement) {

    aResult.Truncate();

    return;

  }

  mElement->GetAttr(kNameSpaceID_None, mAttrAtom, aResult);

}

DocGroup*

nsDOMTokenList::GetDocGroup() const

{

  return mElement ? mElement->OwnerDoc()->GetDocGroup() : nullptr;

}

JSObject*

nsDOMTokenList::WrapObject(JSContext *cx, JS::Handle<JSObject*> aGivenProto)

{

  return DOMTokenList_Binding::Wrap(cx, this, aGivenProto);

}